1. cl Field of the Invention
The present invention relates to a golf club head.
2. Description of the Related Art
It is a common practice to form a plurality of parallel linear grooves in the face surface of a golf club head to extend in the toe-to-heel direction (for example, Japanese Patent Laid-Open Nos. 10-108927 and 7-163688). These grooves are called, for example, scorelines, marking lines, or face lines (they will be referred to as scorelines in this specification). The face surface has a considerable influence on the impact performance. For this reason, techniques of forming a golf club head using a plurality of types of materials to improve an impact feel and the spin amount or flight distance of a struck golf ball have been proposed (for example, Japanese Patent Laid-Open Nos. 10-108927, 7-163688, and 2001-293115).
In general, if a golf club head is formed by a relatively soft material such as soft iron, an impact feel improves. However, when a soft material is used, portions surrounding scorelines are likely to wear. As portions surrounding scorelines wear more severely, the spin amount on a struck golf ball decreases. If a golf club head is formed by a hard material, portions surrounding scorelines become harder to wear, but an impact feel deteriorates.